scholarly journals Foundations of Biology

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1701
Author(s):  
Jean-Louis Sikorav ◽  
Alan Braslau ◽  
Arach Goldar
Keyword(s):  
Natural Selection ◽  
Deductive Reasoning ◽  
Laws Of Nature ◽  
Logical Structure ◽  
Principle Of Sufficient Reason ◽  
Physico Chemical ◽  
Logical Content ◽  
The Origin Of Life ◽  
Living Organisms ◽  
Biological Entities

It is often stated that there are no laws in biology, where everything is contingent and could have been otherwise, being solely the result of historical accidents. Furthermore, the customary introduction of fundamental biological entities such as individual organisms, cells, genes, catalysts, and motors remains largely descriptive; constructive approaches involving deductive reasoning appear, in comparison, almost absent. As a consequence, both the logical content and principles of biology need to be reconsidered. The present article describes an inquiry into the foundations of biology. The foundations of biology are built in terms of elements, logic, and principles, using both the language and the general methods employed in other disciplines. This approach assumes the existence of a certain unity of human knowledge that transcends discipline boundaries. Leibniz’s principle of sufficient reason is revised through a study of the complementary concepts of symmetry and asymmetry and of necessity and contingency. This is used to explain how these concepts are involved in the elaboration of theories or laws of nature. Four fundamental theories of biology are then identified: cell theory, Darwin’s theory of natural selection, an informational theory of life (which includes Mendel’s theory of inheritance) and a physico-chemical theory of life. Atomism and deductive reasoning are shown to enter into the elaboration of the concepts of natural selection, individual living organisms, cells, and their reproduction, genes, as well as catalysts and motors. This work contributes to clarify the philosophical and logical structure of biology and its major theories. This should ultimately lead to a better understanding of the origin of life, of system and synthetic biology, and of artificial life.

scholarly journals Green Plasmonic Nanoparticles and Bio-Inspired Stimuli-Responsive Vesicles in Cancer Therapy Application

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1083 ◽  
Author(s):  
Valeria De Matteis ◽  
Loris Rizzello ◽  
Mariafrancesca Cascione ◽  
Eva Liatsi-Douvitsa ◽  
Azzurra Apriceno ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Anticancer Agents ◽  
Chemical Properties ◽  
Dark Side ◽  
Stimuli Responsive ◽  
Ag Nps ◽  
Au Nps ◽  
Physico Chemical ◽  
Living Organisms ◽  
Biological Entities

In the last years, there is a growing interest in the application of nanoscaled materials in cancer therapy because of their unique physico-chemical properties. However, the dark side of their usability is limited by their possible toxic behaviour and accumulation in living organisms. Starting from this assumption, the search for a green alternative to produce nanoparticles (NPs) or the discovery of green molecules, is a challenge in order to obtain safe materials. In particular, gold (Au NPs) and silver (Ag NPs) NPs are particularly suitable because of their unique physico-chemical properties, in particular plasmonic behaviour that makes them useful as active anticancer agents. These NPs can be obtained by green approaches, alternative to conventional chemical methods, owing to the use of phytochemicals, carbohydrates, and other biomolecules present in plants, fungi, and bacteria, reducing toxic effects. In addition, we analysed the use of green and stimuli-responsive polymeric bio-inspired nanovesicles, mainly used in drug delivery applications that have revolutionised the way of drugs supply. Finally, we reported the last examples on the use of metallic and Au NPs as self-propelling systems as new concept of nanorobot, which are able to respond and move towards specific physical or chemical stimuli in biological entities.

Water Pollution and Its Impact on Environment of Society

2016 ◽  
Vol 3 (5) ◽  
Author(s):  
N. Thyagaraju
Keyword(s):  
Water Pollution ◽  
Pollution Prevention ◽  
Human Beings ◽  
Individual Level ◽  
The Public ◽  
The Government ◽  
Living Organisms ◽  
Set Up ◽  
Biological Entities ◽  
Micro Organisms

The present seminar paper mainly highlight  the concept of  water pollution, causes of water pollution,  Its Effects, Elements of  pollutants, Methods  used to prevent the water pollution in environment  and the mandatory initiatives taken by the concerned authorities for prevention of  water pollution. Water   is essential for survival of all living organisms on the earth. Thus for human beings and plants to survive on land, water should be easily accessible. The term “Pollution” is generally refers to addition of any foreign body either living or non – living or deletion of anything that naturally exists. The basic Sources of Water pollution causes due to Culmination into lakes, rivers, ponds, seas, oceans etc. Domestic drainage and sanitary waste, Industrial drainage and sewage, Industrial waste from factories, Dumping of domestic garbage, Immersion of Idols made of plaster of Paris, Excess use of Insecticides , pesticides, fungicides, Chemical fertilizers, Soil erosion during heavy rains and floods, Natural disasters, tsunami etc. General pollutants  which are also caused for water pollution  which include Organic, Inorganic, and Biological entities, Insecticides, Pesticides, Disinfectants ,Detergents, Industrial solvents, Acids, Ammonia fertilizers, heavy metals, Harmful bacteria, Virus, Micro –Organisms and worms, Toxic chemicals. Agricultural lands become infertile and thereby production also drops, Spread of epidemic diseases like Cholera, Dysentery, Typhoid, Diarrhea, Hepatitis, Jaundice etc. The  basic responsibility of the Government, NGOs, National Pioneer scientific Research Institutions may conduct  research oriented programs on control of water pollution by create  awareness among the public through mass media and Environmental Education on recycling units,  and  water treatment plants must be established both at domestic levels and Industry levels, Every citizen must feel responsible to control water pollution. There have been many water pollution prevention acts that have been set up by the governments of the world. But these are not enough for permanent water pollution solutions. Each of us needs to take up the responsibility and do something at an everyday at individual level. Otherwise we can’t survive in a society forever in a future. 

scholarly journals Estimating Environmental Contamination and Element Deposition at an Urban Area of Central Italy

Urban Science ◽  
2019 ◽  
Vol 3 (3) ◽  
pp. 76 ◽  
Author(s):  
Stefano Loppi ◽  
Adelmo Corsini ◽  
Luca Paoli
Keyword(s):  
Urban Area ◽  
Environmental Contamination ◽  
Urban Areas ◽  
Central Italy ◽  
Protective Role ◽  
Evernia Prunastri ◽  
Physico Chemical ◽  
Living Organisms ◽  
Study Sites ◽  
Economic Constraints

Air quality monitoring in many urban areas is based on sophisticated and costly equipment to check for the respect of environmental quality standards, but capillary monitoring is often not feasible due to economic constraints. In such cases, the use of living organisms may be very useful to complement the sparse data obtained by physico-chemical measurements. In this study, the bioaccumulation of selected trace elements (Al, As, Cd, Ce, Cr, Cu, Fe, Ni, Pb, S, Sb, Zn) in lichen samples (Evernia prunastri) transplanted for three months at an urban area of Central Italy was investigated to assess the main environmental contaminants, their sources, and the fluxes of element depositions. The results pinpointed Cu and Sb as the main contaminants and suggested a common origin for these two elements from non-exhaust sources of vehicular traffic, such as brake abrasion. Most study sites were, however, found to be subjected to low or moderate environmental contamination, and the lowest contamination corresponded to the main green areas, confirming the important protective role of urban forests against air pollution. Ranges of estimated mean annual element deposition rates in the study area were similar or lower than those reported for other urban areas.

Heterochrony and the Problem of Missing Links in Evolutionary Sequences

1984 ◽  
Vol 1 ◽  
pp. 84-96 ◽  
Author(s):  
Thomas W. Broadhead ◽  
Johnny A. Waters
Keyword(s):  
Natural Selection ◽  
Feature Recognition ◽  
Biological Meaning ◽  
Juvenile Stages ◽  
Transitional Forms ◽  
Living Organisms ◽  
Taxonomic Groups ◽  
Organic Change

Critics of the concept of organic change through time have demanded proof not only of “transitional forms” but of specific transitions among higher taxonomic groups. Transitional forms among species and between a species of one genus and a species of another genus have been criticized because most demonstrated ancestor-descendant transitions are considered to occur within one “kind” of organism; the “kind” concept is bereft of biological meaning.Natural selection acts upon organisms at all stages of ontogeny, and especially at larval-juvenile stages. Large shifts in the morphology of one or more features are common in groups of organisms that evolve by heterochrony. Because heterochrony involves a change in timing of the appearance or development of a particular feature, recognition of heterochrony requires a confident knowledge of ontogeny. The resulting increase in complexity (e.g. recapitulation) or decrease in complexity (e.g. paedomorphosis), well documented among living organisms, commonly excludes morphologic intermediates. Paedomorphosis is especially important in the evolution of progressively simplifying lineages and has been well documented from living plants and animals and fossil representatives of echinoderms (blastoids, crinoids), conodonts, arthropods, mollusks and vertebrates. Heterochrony characterizes the evolution of most metazoan organisms, occurs at all taxonomic levels and was probably responsible for major innovations by which higher taxonomic groups are recognized.

scholarly journals Constructor theory of life

2015 ◽  
Vol 12 (104) ◽  
pp. 20141226 ◽  
Author(s):  
Chiara Marletto
Keyword(s):  
Natural Selection ◽  
Evolutionary Theory ◽  
Digital Information ◽  
Evolution Theory ◽  
Physical Processes ◽  
Darwinian Theory ◽  
Gene Replication ◽  
Theory Of Information ◽  
Living Organisms

Neo-Darwinian evolutionary theory explains how the appearance of purposive design in the adaptations of living organisms can have come about without their intentionally being designed. The explanation relies crucially on the possibility of certain physical processes : mainly, gene replication and natural selection . In this paper, I show that for those processes to be possible without the design of biological adaptations being encoded in the laws of physics, those laws must have certain other properties. The theory of what these properties are is not part of evolution theory proper, yet without it the neo-Darwinian theory does not fully achieve its purpose of explaining the appearance of design. To this end, I apply constructor theory's new mode of explanation to express exactly within physics the appearance of design, no-design laws, and the logic of self-reproduction and natural selection. I conclude that self-reproduction, replication and natural selection are possible under no-design laws, the only non-trivial condition being that they allow digital information to be physically instantiated. This has an exact characterization in the constructor theory of information. I also show that under no-design laws an accurate replicator requires the existence of a ‘vehicle’ constituting, together with the replicator, a self-reproducer.

What is life?

1997 ◽  
Author(s):  
John Maynard Smith ◽  
Eors Szathmary
Keyword(s):  
Natural Selection ◽  
Origin Of Life ◽  
Definition Of Life ◽  
The Sun ◽  
Physical Processes ◽  
Living Things ◽  
Survival And Reproduction ◽  
The Origin Of Life ◽  
Definition Of ◽  
Life On Earth

Imagine that, when the first spacemen step out of their craft onto the surface of one of the moons of Jupiter, they are confronted by an object the size of a horse, rolling towards them on wheels, and bearing on its back a concave disc pointing towards the Sun. They will at once conclude that the object is alive, or has been made by something alive. If all they find is a purple smear on the surface of the rocks, they will have to work harder to decide. This is the phenotypic approach to the definition of life: a thing is alive if it has parts, or ‘organs’, which perform functions. William Paley explained the machine-like nature of life by the existence of a creator: today, we would invoke natural selection. There are, however, dangers in assuming that any entity with the properties of a self-regulating machine is alive, or an artefact. In section 2.2, we tell the story of a self-regulating atomic reactor, the Oklo reactor, which is neither. This story can be taken in one of three ways. First, it shows the dangers of the phenotypic definition of life: not all complex entities are alive. Second, it illustrates how the accidents of history can give rise spontaneously to surprisingly complex machine-like entities. The relevance of this to the origin of life is obvious. In essence, the problem is the following. How could chemical and physical processes give rise, without natural selection, to entities capable of hereditary replication, which would therefore, from then on, evolve by natural selection? The Oklo reactor is an example of what can happen. Finally, section 2.2 can simply be skipped: the events were interesting, but do not resemble in detail those that led to the origin of life on Earth. There is an alternative to the phenotypic definition of life. It is to define as alive any entities that have the properties of multiplication, variation and heredity. The logic behind this definition, first proposed by Muller (1966), is that a population of entities with these properties will evolve by natural selection, and hence can be expected to acquire the complex adaptations for survival and reproduction that are characteristic of living things.

The Perennial Riddle of Life’s Origin

2021 ◽  
pp. 82-96
Author(s):  
Franklin M. Harold
Keyword(s):  
Natural Selection ◽  
Electron Transport ◽  
Atp Synthase ◽  
Hydrothermal Vents ◽  
Rna World ◽  
Good Reason ◽  
Dynamic Network ◽  
Electron Transport Chains ◽  
The Origin Of Life

The origin of life is the most consequential problem in biology, possibly in all of science, and it remains unsolved. This chapter summarizes what has been learned and highlights questions that remain open, including How, Where, When, and especially Why. LUCA, some four billion years ago, already featured the basic capacities of contemporary cells. These must have evolved still earlier, at a nebulous proto-cellular stage. There is good reason to believe that enzymes, DNA, ribosomes, electron-transport chains, and the rotary ATP synthase all predate LUCA and were shaped by the standard process of variation and natural selection, but we know next to nothing about how cells ever got started. I favor the proposal that it began with a purely chemical dynamic network capable of reproducing itself, that may have originated by chance. Natural selection would have favored the incorporation of any ancillary factors that promoted its kinetic stability, especially ones that improved reproduction or gave access to energy. All the specifics are in dispute, including the role of a prebiotic broth of organic chemicals, the nature and origin of enclosure, the RNA world, and a venue in submarine hydrothermal vents. My sense is that critical pieces of the puzzle remain to be discovered.

Effect of low-dose exposure of aluminium oxide nanoparticles in Swiss albino mice: Histopathological changes and oxidative damage

2020 ◽  
Vol 36 (8) ◽  
pp. 567-579
Author(s):  
Arpita De ◽  
Swarupa Ghosh ◽  
Manoswini Chakrabarti ◽  
Ilika Ghosh ◽  
Ritesh Banerjee ◽  
...  
Keyword(s):  
Dna Damage ◽  
Oxidative Damage ◽  
Redox Homeostasis ◽  
Aluminium Oxide ◽  
Hydrodynamic Diameter ◽  
Oxide Nanoparticles ◽  
Physico Chemical ◽  
Living Organisms ◽  
Aluminium Oxide Nanoparticles

Rapid growth in the use of aluminium oxide nanoparticles (Al2O3 NPs) in various fields such as medicine, pharmacy, cosmetic industries, and engineering creates concerns since the literature is replete with data regarding their toxicity in living organisms. The objective of the present study was to demonstrate the potential toxicological manifestations of repeated exposure to Al2O3 NP at low doses in vivo. In the present study, Al2O3 NP was orally administered at 15, 30 or 60 mg kg−1 body weight for 5 days to Swiss albino male mice. A battery of well-defined assays was undertaken to evaluate aluminium (Al) bioaccumulation, haematological and histological changes, oxidative damage and genotoxicity. Physico-chemical characterisation demonstrated increases in hydrodynamic diameter along the concentration gradient of Al2O3 NP dispersed in MilliQ water. Brain, liver, spleen, kidney and testes showed high Al retention levels. Histopathological lesions were prominent in the brain and liver. Al2O3 NP treatment increased levels of lipid peroxidation and decreased glutathione content in the test organs at all dose levels. The enzyme activities of catalase and superoxide dismutase were also significantly altered. DNA damage quantified using the comet assay was markedly increased in all the soft organs studied. Anatomical abnormalities, redox imbalance and DNA damage were positively correlated with Al retention in the respective organs. Size, zeta potential and colloidal state might have contributed to the bio-physico-chemical interactions of the NPs in vivo and were responsible for the non-linear dose response. The overall data indicate that Al2O3 NP exposure may result in adverse health consequences, inclusive of but not limited to disturbed redox homeostasis, hepatocellular toxicity, neurodegeneration and DNA damage.

scholarly journals Separation of Biological Entities from Human Blood by Using Magnetic Nanocomposites Obtained from Zeolite Precursors

Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1803
Author(s):  
Serena Esposito ◽  
Antonello Marocco ◽  
Gianfranco Dell’Agli ◽  
Barbara Bonelli ◽  
Franca Mannu ◽  
...  
Keyword(s):  
Human Blood ◽  
Chemical Properties ◽  
Industrial Process ◽  
High Sensitivity ◽  
Point Of View ◽  
The Novel ◽  
Magnetic Adsorbents ◽  
Physico Chemical ◽  
Magnetic Metal ◽  
Biological Entities

In this work, three novel magnetic metal–ceramic nanocomposites were obtained by thermally treating Fe-exchanged zeolites (either A or X) under reducing atmosphere at relatively mild temperatures (750–800 °C). The so-obtained materials were thoroughly characterized from the point of view of their physico-chemical properties and, then, used as magnetic adsorbents in the separation of the target gene factors V and RNASE and of the Staphylococcus aureus bacteria DNA from human blood. Such results were compared with those obtained by using a top ranking commercial separation system (namely, SiMAG-N-DNA by Chemicell). The results obtained by using the novel magnetic adsorbents were similar to (or even better than) those obtained by using the commercial system, both during manual and automated separations, provided that a proper protocol was adopted. Particularly, the novel magnetic adsorbents showed high sensitivity during tests performed with small volumes of blood. Finally, the feasible production of such magnetic adsorbents by an industrial process was envisaged as well.

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